Dynamic mathematical model for biotransformation and mass transfer of livestock generated voc-odor in a bioactive dust particle system

A multi-step mass transfer-biodegradation model is developed to describe th e bioactive adsorber dynamics for the biotreatment of livestock generated o dor causing VOCs (VOC-odor) based on a biologically active dust particle (B ADP) proc ess. The BADP process employs dust particles with adsorbat-acclim ated microbial culture to form the bioactivated dust particles (BDP) for th e simultaneously adsorption, mass transfer, and biodegradation of VOC-odor. The model incorporating age and size distributions of BDP considers the eq uilibrium partitioning of VOC-odor at BDP and bulk gas interface that follo wed by two kinetic processes occurring in the bulk and solid phases: bulk g as mass transfer-biodegradation and BDP biofilm diffusion-biodegradation. A nalytical equations indicate that the overall biotransformation rate of VOC -odor in a BADP process is controlled by BDP-bulk gas equilibrium processes represented by the slowest of two kinetic processes determined by a dimens ionless group: the Thiele modulus (Phi(2)), the Damkohler number (Da) and t he Blot number (Bi). Computer simulations demonstrate that the most favorab le performance of a BADP system in reducing VOC-odor concentrations is oper ated under Bi < 1, Da < 1, or Bi > 1 Phi(2) < 1; indicating diffusion-biode gradation controlled. The dimensionless group can be used to identify the d ominant rate-limiting processes and to evaluate the overall biomineralizati on rate in a BADP process. Simulation results allow the determination of pr eliminary design for prototype development.